The Study And Application Of Transmission-model Optical Monitoring Technology Of Dust Density

Nowadays, people have increasingly paid much attention to the pollution problem such as soot in the atmosphere, so the monitoring technology of the density of soot isdeveloping rapidly. The transmission-model optical measurement has a wide application because this method has a short measurement period, does not interfere the measuring field, and is easy to realize online real-tune monitor. But this method is apt to be interfered with the external environment in the course of measuring, and finally leads to the inaccurate result.On the basis of analyzing the principle and the basic system of the transmission-model optical online monitor emphatically, we have made an experiment with the dust of anthracite and gas coal to derive the relation between light extinct coefficient and dust density, particle size and density of the material. Consequently, an experiential formula has been got which can guide confirming of light extinct coefficient in the actual measurement. Various kinds of factors that may bring errors to the result of measuring have also been analyzed. Applying two-beam-optics to the transmission-model optical measurement of dust density, we have confirmed that the traditional difference method can not clean up the influence of light source fluctuating, temperature change etc. So a new thought of two-beam-optics difference method has been put forward, and it's feasibility has been verified. We also have mended the design of the system and confirmed the measuring process. Through making the experiment to compare among capacity of error canceling of single-beam-optics, traditional two-beam-optics difference and the new two-beam-optics difference method, the dependability of improved transmission-model optical measuring system has been verified.By applying this kind of transmission-model two-beam-optical on-line monitoring system of dust density to the high-voltage electrostatic dust-collecting system, thesystem based on the signal of dust density has realized the real-time control of the electrostatic precipitator which automatic level has been improved, and has technical and great economic significance.